The conventional packaging process of Fine-Pitch Ball Grid Array (FBGA) products is shown in FIG. 1: S100: chip attachment; S102: wire bonding; S104: molding and curing; S106: ball mounting; S108: singulation. In the step S104, the molding process is to inject a molding compound into a mold chase at high temperature and high pressure, so that the molding compound covers the entire top surface of the substrate, has polymeric cross-linking reactions, and then is cured, to attain a purpose of protecting the bonding wires and improving the reliability of the devices. FIG. 2 is a side view of the packaging structure in the prior art, and FIG. 3 is a top view of the packaging structure in the prior art, wherein, the symbol 10 indicates the substrate, the symbol 12 indicates the chip, the symbol 14 indicates the bonding wires, the symbol 16 indicates the molding compound, and the symbol 18 indicates the solder ball array. However, that process is time-consuming, the mold chase is difficult to design, and the molding process is complex and involves high cost and high molding material consumption.